Year	% of total fuel combustion
1971	0.12277470841006753
1972	0
1973	0
1974	0
1975	0.17699115044247787
1976	1.0195412064570943
1977	0.47095761381475665
1978	0.5970149253731344
1979	0.07052186177715092
1980	35.50335570469799
1981	33.96596858638744
1982	34.85401459854015
1983	37.564322469982855
1984	41.738629821531376
1985	41.30808950086058
1986	41.287284144427
1987	39.898053753475445
1988	31.435406698564595
1989	35.30079455164585
1990	32.56616800920599
1991	36.59250585480094
1992	38.2918552036199
1993	34.154429180483184
1994	31.524989320803076
1995	37.99635701275045
1996	35.610229847847194
1997	36.21874141247595
1998	34.07112658542651
1999	34.144524459895706
2000	32.632293080054275
2001	33.67493338798934
2002	32.044778730103204
2003	32.55389718076285
2004	31.018518518518523
2005	30.408395498798836
2006	29.65237685787987
2007	29.90310725025058
2008	35.007429420505204
2009	34.89247311827957
2010	32.96058371004838
2011	34.22246994187435
2012	33.94260060926728
2013	34.27934163974773
2014	33.752006140534505
